Sensitivity And Specificity; What Is Sensitivity And Specificity - Interacoustics Sera Additional Information

Sensitivity and specificity

What is sensitivity and specificity?

Sensitivity and specificity are common words used when discussing newborn hearing screening given the
importance of detecting those children with a potential hearing loss who require further diagnostic
assessment and treatment.
In a medical diagnosis:
Sensitivity refers to the probability that a test will be positive when the disease is present (true positive).
Specificity refers to the probability that a test will be negative when the disease is not present (true
negative).
These terms can often be confusing in the field of hearing screening. This may be due to the fact that
hearing screening instruments label the outcome of a test where "normal" hearing was detected as a "pass"
whereas the definition above refers to labelling a test that detects a disease as "positive" and non-diseased
or normal as "negative".
Essentially, hearing screening products should have a high sensitivity, meaning they should be good in
detecting patients with a disease (a potential hearing loss) and labelling the result as a REFER. They also
need to have a high specificity, ensuring patients without the disease (normal hearing) are not unnecessarily
sent on for further diagnostic testing when it was not required.
Sensitivity is principally determined by the instrument implementation (algorithms and hardware). Poor
sensitivity leads to unwanted false passes and can have very serious consequences for the child, as they
would not receive timely and adequate treatment or amplification, leading to potential language development
and social issues.
Specificity is also a measure of instrument implementation, however it also heavily influenced by the test
environment, the tester and the test procedure. Therefore, the specificity quoted by one screening program
with highly trained screeners who screen babies in a quiet room 12-24 hours after the child's birth, may differ
from another screening program where staff have limited training, babies are tested in noisy test
environments or within hours of being born. Poor specificity (or false refers) can lead to an increased cost to
screening programs requiring babies to be rescreened numerous times or being sent for unnecessary costly
diagnostic assessments. It also leads to increased anxiety for parents or caregivers.
D-0114042-D – 2020/03
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